Frequently, when producing hydrocarbon fluids, e.g., oil and/or gas, from a formation, solids are produced along with the fluids. These solids can range in particle size from very fine silt to very coarse grained material, depending on the nature of the formation. Formations that produce solids vary from totally unconsolidated (uncemented) to weakly cemented. Formations having significant compressive strength of about 500 psi or greater, do not produce solids under normal operating conditions.
Various techniques are employed for controlling the production of these solids. One such technique is called gravel packing. Gravel packing involves filling an annulus or annular space between a casing and a retaining screen with a sieved particulate such as sand, the casing having been previously perforated. For best results for well productivity, sand also is placed into and through the perforation tunnels using pumping techniques. Subsequently, as the well is produced, sand serves as a filter media to restrain the movement and production of formation solids. The screen, in turn, prevents the movement of the sieved sand or "gravel".